The broad, long term objective of this proposal is to examine whether non-traditional emergency medical services (EMS) resources (e.g., nurse advice telephone services, assisted transportation) may be provided to 911 callers without jeopardizing patient safety. The specific aims are 1) to develop decision guidelines from information already gathered by 911/EMS dispatchers in a large urban center that could allow dispatchers to distinguish between adult callers (age greater than 15) with an immediate need for an emergency medical technician (EMT) -paramedic response and those who could receive non-traditional services; 2) to validate prospectively the dispatch guidelines developed in specific aim 1; and 3) to estimate the potential benefits versus risks of such guidelines. The health relatedness of the project is an examination of new patient triage strategies being proposed in response to increasing managed care penetration. Such strategies would attempt to match emergency resources more specifically to patient need. These approaches require careful study prior to implementation. The research design is a cross sectional examination, using both retrospective and prospective approaches, of three dispatch assigned "nature/severity" codes to determine if sufficient information is gathered and can be organized to identify callers for whom non-traditional EMS resources may be provided. The methods are 1) a retrospective analysis of 284 dispatched cases matched to the corresponding paramedic field record. Logistic regression will be used to develop dispatcher decision guidelines. 2) Prospective methods will be used to validate and assess criteria risks and benefits. Sensitivity, specificity, and positive and negative predictive values will be used to make this assessment. During the prospective phase dispatchers will apply the criteria in the live dispatch environment and document patient categorization (EMS or non- traditional EMS needs) as though the criteria were in place, however no changes in dispatch practices will be made.